(2)It shall not be necessary in any case to prove the signature or official character of the person appearing to have signed such deposition; and a certificate by such person that the defendant or person accused had an opportunity of cross-examining the witness, and that the deposition, if made in a criminal proceeding, was made in the presence of the person accused, shall, unless the contrary is proved, be sufficient evidence that he had that opportunity and that it was so made.
